Right triangle: circumradius and altitude to the hypotenuse given, find the area

The same question, asked 2 times: CDS 2 2020*, CDS 2 2021. Every wording below, oldest first.

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Question 1
CDS 2 2020
70 $What is the area of a right-angled triangle, if the radius of the circumcircle is 5 cm and altitude drawn to the hypotenuse is 4 cm ?$
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Question 2
CDS 2 2021
61 $The radius of circum-circle of a right-angled triangle is 10 cm and the altitude drawn to the hypotenuse is 8 cm. What is the area of the triangle ?$
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